[Bad89stang]

What are the rules as far as relocating your battery to the trunk in an '89 coupe/notchback? I have a panel behind the rear seats that is bolted to the metal crossbars and is carpeted. It is not airtight though. Just holds my amp out of the way. I don't want to have to spend $100 on the Moroso blue box if I don't need to. Is it legal to put a normal black covered battery box in the trunk and still race? I know that it has to be bolted down. What else?